Differential mode filtering

AN4304

8/20

DocID024731 Rev 1

Figure 7: "Differential voltage with a differential filter of 8 kHz" shows the signal between

pin+ and pin- of the TSC103. The high frequency has been correctly filtered.

Figure 7: Differential voltage with a differential filter of 8 kHz

However, the common mode voltage has not been filtered. Even if the TSC103 has an

excellent CMRR (see Figure 17: "CMRR vs. frequency") of up to 200 kHz, it is important to

also remove the high frequency which might cause incorrect behavior (see Figure 8: "Input

pin+ voltage with a differential filter of 8 kHz").

Figure 8: Input pin+ voltage with a differential filter of 8 kHz

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